Keitele

Etymology 1
From a farm name, which may have been named after the lake, despite the fact that the town and lake are located at least 10 km (6 mi) away.

Etymology 2
An amalgamation (blend) of (dialectally also "isthmus") and dialectal, , and thus the lake is named after a particular isthmus (possibly reference to a peninsula that is now called Niininiemi).